Chem 3A
posted by shylo .
please help me with this chemistry problem.
HalfLife
A radium226 sample initially contains 0.112 mol. How much radium226 is left in the sample after 6400 years? The halflife of radium226 is 1600 years.

6400 years is 4 halflives. The amount remaining is
0.112 mol * (1/2)^4
= 0.112/16 = 0.007 mol